Baking Ammonia: The Other White Leavening Agent - "According to the ubiquitous "Food Lover's Companion" by Sharon T. Herbst, baking ammonia is a chemical leavening agent that is considered "the precursor of today's baking powder and baking soda." It has also been known as ammonia bicarbonate, ammonia carbonate, ammonium bicarbonate and hartshorn in various circles and at different points in time. Traditionally, baking ammonia was a by-product of hartshorn, which used to be obtained by grating or calcining the horns of harts, which in modern times we know as male deer" (Food Product Design). Learn more...
The video below (How Leavening Works) explains leavening agents and its function in a very simple manner. I like it Dr Kiki!
How Leavening Works